[[UINavigationBar appearance] setTintColor:[UIColor whiteColor]]; // 返回按钮颜色

[UINavigationBar appearance].barTintColor = YK_BUTTON_COLOR; //背景颜色

[[UINavigationBar appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:[UIColor whiteColor],NSForegroundColorAttributeName,[UIFont boldSystemFontOfSize:17],NSFontAttributeName, nil]]; //标题title属性

 /*自定义标题*/

UILabel *vTitleLable = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 200, 21)];

    vTitleLable.font = [UIFont boldSystemFontOfSize:17];

    vTitleLable.textColor = [UIColor whiteColor];

    vTitleLable.textAlignment = NSTextAlignmentCenter;

    vTitleLable.backgroundColor = [UIColor clearColor];

    vTitleLable.text = _titleStr;

    [self.navigationItem setTitleView:vTitleLable];

  /*自定义返回按钮*/

  UIBarButtonItem *vLeftButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:@selector(backButtonClicked:)];

    self.navigationItem.leftBarButtonItem = vLeftButtonItem;

   [vLeftButtonItem release];